Single-institution experience with solid pseudopapillary neoplasm of the pancreas

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare clinical entity. The objective of this study was to review a single institution's experience with this uncommon tumor, as well as review the literature.

Consecutive patients, who underwent surgery for a pathologically confirmed SPN between 1991 and 2010, were retrospectively reviewed. A PubMed search (January 1980-June 2011) was conducted to identify risk factors for death among SPN patients.

The institutional review identified 16 patients with SPN. Thirteen patients were female and three patients were male (median age 34 years). All patients underwent radical resection. Two patients had metastatic disease at the time of operation as evident by the presence of lymph node metastasis and gallbladder metastasis. One developed liver metastasis 4 months postoperatively and subsequently died. The other patient received adjuvant chemotherapy (gemcitabine and capecitabine), and 23 months after the initial operation, no tumor recurrence was detected and the patient is still alive. All other patients remain disease-free. Analysis of 29 fatalities reported in the English literature (including the present case) revealed several atypical features including male gender, old age, tumor size >5 cm, diffuse growth pattern, cellular or nuclear atypia, high mitotic rate, extensive necrosis, extrapancreatic invasion, metastasis and incomplete resection.

SPN is not always indolent. Male patients and those with old age, atypical histopathology (large tumors, diffuse growth, cellular/nuclear atypia, mitotic activity, necrosis, invasion/metastasis) and incomplete resection may have a higher risk of recurrence and death, deserving particular attention.